The need to disinfect and sanitize swimming pools is an ongoing responsibility of persons who wish to swim in clean pool water. Chlorine is an oxidizing agent that has been commonly used for such a purpose, and whilst it is generally effective, it has many drawbacks. The odour and taste of chlorinated water (even at the low concentrations used in pool water) are not appealing, and large quantities of chlorine pre-mix are required.
A little known approach to large scale drinking water treatment based on oxidizing agents is to supply hydrogen peroxide to ozonated water (in a process that produces an equilibrium state referred to as “peroxone”).
Highly reactive hydroxyl free radicals are a product of the peroxone process, and it is these hydroxyl radicals that are the primary oxidizing agents involved in contaminant disinfection and sanitization of water. Although hydroxyl radicals are produced during the spontaneous decomposition of ozone (to cause “direct oxidation” of contaminants in water), an even greater concentration of hydroxyl radicals may be produced by accelerating the rate of ozone decomposition by the addition of hydrogen peroxide thereto (to cause “indirect oxidation” of contaminants in water). A higher hydroxyl radical concentration will increase the oxidation rate.
It has now been found by the present inventor that the peroxone process may be applied to the disinfection and sanitization of water stored in smaller reservoirs than those used in large scale drinking water storage, with the use of an apparatus and method that supplies hydrogen peroxide to ozonated water at a controllable rate.